Electric resistance device



Feb. 1'1, 193s. v E. R. MORTON -2,030,460

ELECTRIC RESI STANCE DEVICE Filed July 20, 1954 1 I INVENTOR E R. MORTON ATTORNEY Patented Feb. 11, 1936 UNITED STATES 2,030,460 nmc'rmc nnsrs'rmca nrzvrcn Edmund R. Morton, New York, N. Y., assignor to Bell Telephone Laboratories,

Incorporated,

New York, N. Y., a corporation of New York Application July 20, 1934, Serial No. 130,147

- ance on its support and terminals are embedded in the core and extend beyond its ends for effecting the winding connections and for connleicting the resistance proper to its operating circ t.

Extending'the terminals beyond the ends of the resistance rather than terminating them on the spoolhead reduces the liability of shorts either to the mounting panel or to adjacently mounted resistance units and permits closer spacing of these units, while the forming of the screw threaded portion integrally with the core and spoolheads avoids the use of other additional securing media and correspondingly reduces the cost of manufacture of the resistance unit.

In the drawing,

Fig. 1 is a plan view of the resistance core without the winding;

Fig. 2 is-a view of the supporting plate showing a number of resistances in position thereon;

Fig. 3 is an enlarged view of the completed resistance showing the core and winding with portions cut away;

Fig; 4 is an enlarged rear end view showing a portion of the supporting plate and the securing nut with portions cut away;

Fig. 5 is an enlarged sectional view taken on line 5--5 of Fig. 3; and

Fig. 6 is an enlarged front end view.

As shown in the drawing, the resistance devices of this invention consist of a mounting of molded insulating material of unit structure in which the core portion I0 is formed integrally with spoolhead portions l2 and I3 and a fastening portion ll. Conductors l9 and 20 are embedded in the .core I0 and protrude from the front spoolprovided to increase the creepage path between the terminals [9 and 20 "at' thatpoint, the extension 2| being formed integrally withthe spoolhead l2.

Similarly the terminals Hand 20 protrude from --from the spirit of the invention and the scope the appended claims.

cult. This fastening end is also provided with an insulating portion 22 for increasing the creepage path between the terminals l9 and 20 at this point. Y

The fastening portion I4 is preferably screw threaded and is provided adjacent the spoolhead II with an octagonal portion I5 for engagement with. a similarly shaped hole IS in a mounting plate I! and serves to preventthe rotating movement of the resistance unit thus formed upon the tightening of nut screw III on screw threaded portion l4.

I As above stated, extending the terminals beyond the extreme ends of the mounting rather than terminating them on the spoolheads reduces the danger of shorts while the forming of the screw threaded portion integrally'with the core and spoolheads avoids the use of other securing media and correspondingly reduces the cost of manufacture of the unit.

The core unit structure maybe formed of ceramic or thermoplastic material and other minor changes may be made without departing What is claimed is:

1. In a resistance device, a core of insulating material having spoolhead portions, a. polygon portion and a screw threaded fastening portion integrally formed therewith, the polygon portion and the screw threaded portion extending from the opposite side of one of said spoolhead portions with respect to the core.

2. In a resistance device, a core of insulating material .having spoolhead portions, a. polygon portion and a fastening portion integrally formed therewith on the opposite side of one of said spoolhead portions with respect to said core and conducting members embedded in the centralportion of said core and protruding from both ends thereof, the spoolhead portion adjacent the polygon portion serving as ,a base for mountin the device on its support.

3. In a resistance device, a, core of insulating material having spoolhead portions, a polygon portion and a screw threaded fastening portion formed integrally therewith and, extending from the opposite side of one of said portions, a plurality of terminals embedded lengthwise in said core and having their ends protruding from said core and said fastening portion, resistance wires wound on said core and slots in one of said spoolheads parallelly disposed with respect to the'di rection of said terminals for leading the ends of said wire toward the protruding ends of said terminal for connection therewith, the spoolhead portion adjacent the polygon portion serving as a base for mounting the device on its support.

4. In a resistance unit, a core'o! molded insulating material having spoolhead portions and a screw threaded fastening portion Iormed integrally therewith, insulating lugs, one 0! said lugs extending from said fastening portion and the other from one 0! said spoolhead portions, a plu- 10 rality of terminals embedded lengthwise in said core, one 01' said terminals its ends protruding from one of sair'. spoolheads and said tastening portion and the other terminals'trom said lug portions, resistance wires wound'on said core and slots in one or said spoolheads for leading the ends of said wire toward the protruding ends of said terminals for connection therewith, said lug portions increasing the 'creepage path between said terminals.

EDMUND R. MORTON, 

